Ticket inspectors on public transport in Melbourne. They may be uniformed or plain clothed but are most commonly found in packs of 3 or 4. The term originates from the former name of Melbourne's public transport body 'The Met' later to become known as 'Metlink'.

"Had to leg it at Broadiestaish after a metdog asked to see me ticket."
"A metdog fined me for not having a Myki on the tram even though there was no machine to buy one from..."